Safety device for vehicle doors



April 26, 1938. F. c. M CLANAHAN 2,115,643

SAFETY DEVICE FOR VEHICLE DOORS Original Filed Feb. 27, 1935 To Ignition5w.

Patented Apr. 26, 1938 UNITED STATES PATENT OFFICE 2,115,643 SAFETYDEVICE FOR VEHICLE nooRs Application February 2'1, .1935, Serial No.8,579 Renewed September 25, 1937 2 Claims.

The purpose of the present invention is to provide safety devices forpreventing the opening of vehicle doors while the vehicle is in motion.One of the most frequent causes of accidents to cars and injury topersons alighting from cars is the opening of the vehicle doors beforethe vehicle is stopped. These accidents are not infrequently due topassing motorists or to the open door being brought into engagement witha parked car. Persons are also frequently injured by being thrown asthey alight from a moving vehicle. More specifically the presentinvention provides an automatic lock for the doors which is releasedonly when the car is brought to a stop.

In addition to providing a safety device 'the invention seeks to providea safety feature which is extremely simple, inexpensive and reliable inthat there are few parts which can get out oi order and fail to functionwhen called upon.

Referring to the accompanying drawing which is made a part hereof and onwhich the same reference characters refer to the same part thruout,

Figure 1 is a side elevation of a motor vehicle of a conventional designhaving my invention incorporated therein,

Figure 2 is an enlarged detail View of the door fastening and releasingmeans,

Figure 3 is a section on line 3-3 of Figure 2,

Figure 4 is an enlarged detail view of the locking plunger,

Figure 5 is a detail view of a cut out switch, and

Figure 6 is a detail view similar to Figure 2 of a modified form of lockreleasing means.

In the drawing numeral it indicates a conventional motor car and ii theintake manifold to the engine. Pipes l2 and it extend from this intakemanifold to a bellows iii. A cut out switch it is positioned in thissuction to provide means for manually breaking the suction on thebellows created by the vacuum produced by the intake suction. A link itis pivotally attached to the inner side of the bellows and attached atits other end to an arm ii on a member it which is pivotally mounted ona- U shaped bracket l9 which latter is secured by bolts or rivets 20 tothe body of the car. In the illustration given the device is designed tolock and release both the front and rear doors 2 and 25 respectively.Obviously it can be used to lock one door only when necessary. To theends of the member it are pivotally attached plungers 2|. These plungersare composed of two telescoping elements which are urged apart by aspring 22. The outer end of the plunger engages in a recess 26 in theedge of the door to prevent opening of the door when the plunger is inlocking position. The end of the plunger is beveled at 21 to permitclosing of the door, the door forcing the outer end of the plunger inagainstthe tension of the spring 22. The cut out switch i3 which isplaced in the suction line H, it permits the operator of the vehicle tobreak the suction and permit opening of the door without stopping theengine. This cut out switch consists of a plunger 28 which normally isin the position shown in Figure 5, being urged to this position byspring 29. When in this position the bore it connects pipes it and it tosubject the bellows to the engine suction. When the plunger is pushed init cuts off pipe it and port ill opens pipe it to atmosphere thruopening 3% so that the bellows is relieved of the suction and thetension of the bellows withdraws the locking plungers for permitting thedoors to be opened. The bellows are made of spring metal so that as soonas the suction is relieved it will spring but and rock the member it towithdraw the plungers.

The operation of the device should be apparent from the descriptiongiven. So long as the englue is running there will be suction created inthe lines it and it which is transmitted to the bellows causing thebellows to hold the plungers in locking position. These plungers do notin any way affect the regular door latches. They mere- 1y make itimpossible to open the doors while the engine is running. As soon as theengine stops the suction is relieved and the doors may be opened in theusual way.

The operator of the vehicle may wish to allow some one in the vehicle toget out without actually stopping the engine. He may do this byoperating the plunger 28. Under such circumstances there will be nodanger since the vehicle will be under the control of the operator.

In the modified form shown in Figure 6 the plungers are operated by asolenoid 32 which is in circuit with the ignition to the engine. A link33 is pivotally connected with a rock lever 34 which lever carriesplungers 35 pivotally attached to its ends. So long as the engine isrunning .the solenoid will be energized and the plungers held in doorlockingposition. As soon as the circuit is broken the plungers areautomatically withdrawn.

It will be obvious to those skilled in the art that many changes may bemade in the invention without departing from the spirit thereof. .1,

therefore. do not limit myself to the specific showing in the drawingnor the description in the specification but only as set forth in theappended claims. 4

What I claim is:

l. A safety device for motor vehicles comprising means for holding thevehicle doors locked when the engine of the vehicle is running and forreleasing the locking means when the engine is stopped, said meanscomprising a locking plunger movable to engage in a recess in the edgeof the door to be locked and having resilient means for withdrawing itfrom locking position, said resilient means including a bellows-havingits interior subject to the engine suction to move the locking plungerto locking position and hold it there as long as the engine is running.

2. The combination with the body of a vehicle having doors thereon, of asafety lock for the doors comprising a bracket mounted on the said body,a lever pivotally mounted on the bracket, a plunger slidable in the bodyand engageable with the doors to lock the doors, a chamber having anelement movable under change of pressure in the chamber, a connectionbetween said element and the said lever, a connection from the interiorof the said chamber for subjecting it to the suction of the motor oi.the vehicle, means for biasing said element in a direction to unlock thesaid plunger when the suction in the chamber is broken and for yieldingunder the suction to permit locking of the plunger when a partial Vacuumis created in the said chamber, whereby the said doors will be lockedwhenever the motor is running and will have the said locking meansreleased automatically when the motor stops.

FREDERICK C. MCCLANAHAN.

